Folding pocket saws are currently available in a wide variety of forms, and generally consist of a handle in which at least one blade is pivotably mounted for movement between a folded or closed position, and an extended or open position in which it is in condition for use. For example, one folding saw that is commercially available includes a pair of blades that are mounted directly in the handle and are stored by folding them into its upper surface; the blades are biased by a spring washer disposed between them on their pivot screw, and a slide lock is provided which is received in a recess in the bottom surface of the handle and is drawn rearwardly to unlock the blades and permit their movement. Another commercially available saw has a blade directly pivoted upon one screw and a latch member pivoted upon a second screw spaced therefrom, the latter acting to lock the blade in position. Folding knives having slide switches operated from the side of the handle are of course also commonly known.
There is as well a considerable body of patent art that is pertinent to the construction of tools having folding blades. Thus, Chilko U.S. Pat. No. 3,404,456 discloses an over-center spring loading arrangement for the folding blade of a saw, by which it is held in either the open or the closed position. A spring loaded lever is employed in the tool shown in Montgomery U.S. Pat. No. 981,786, which functions to lock the blade in either of two open, as well as its closed, position. A pruning saw with a spring-loaded locking bolt is disclosed in Santoyo U.S. Pat. No. 1,638,749, and in U.S. Pat. No. 692,092 Upham shows a pocket knife with folding blades, which apparently are held in position by conventional spring loading means.
Each of the following U.S. patents utilizes some form of mechanical lock to retain a blade in extended position: Finlay U.S. Pat. No. Des. 257,943; Koskela U.S. Pat. No. 2,736,354; Behlefeldt U.S. Pat. No. 2,747,631 (multiple blade positions); Dowdy et al U.S. Pat. No. 2,904,373 (a water-tight compartment also being provided within the handle); Herman et al U.S. Pat. No. 3,245,445; and Bush U.S. Pat. No. 252,179. Tyler U.S. Pat. No. 698,764 shows a folding saw in which the blade is partially received within the handle, and a combination tool is disclosed in Haag U.S. Pat. No. 784,674, which has a saw blade formed with apertures to receive a detent for locking it in each of several pivoted positions. European Patent application No. 100 377 discloses a folding knife construction in which a number of blades rotate about a common pivot, spring action being employed to hold them in open or closed positions, and German Offenlegungsschrift DE No. 33 24 637 discloses a folding pocket knife construction in which a spring loaded member cooperates to secure the blades.
Despite the rather extensive activity in the art indicated by the foregoing, a need remains for a sturdy and durable pocket tool, which is relatively facile and inexpensive to manufacture and in which interchangeable blades of various types can readily and securely be mounted, for movement between open and closed positions and for highly effective use.
Accordingly, it is an object of the present invention to provide a novel handle assembly for a tool having interchangeable fold-away blades, which is sturdy and durable and yet relatively facile and inexpensive to manufacture.
It is also an object of the invention to provide such a handle assembly in which blades of various types can readily and securely be mounted for highly effective and convenient use.
It is another object of the invention to provide such an assembly wherein the head member on which the blades are mounted can be secured in both its open and closed positions in a simple and yet effective manner, and from which the mounted blade can conveniently be unfolded to its operative position.
Yet another object of the invention is to provide such a handle assembly wherein the body of the handle serves not only to contain the folded blade but also to store a supply of replacement blades.
Additional objects concern the provision of a novel tool employing a handle assembly having the foregoing features and advantages.